Positive Ion Chemistry of Acetylene and Methylacetylene Clusters. Formation of Benzene and C2nH2n+ Ions via Intracluster Polymerization Reactions
Abstract
We report the observation of large (n up to -25) acetylene and methylacetylene cluster ions- the largest yet reported from ionization of neutral (C2H2)n or (CH3CCH)n clusters. The cluster ion intensity distributions of both systems display prominent magic numbers at n = 3. This finding is indicative of intraclusters ion-molecule reactions giving rise to what are most likely benzene and trimethylbenzene ions from (C2H2)n+ and (CH3CCH)n+ cluster ions, respectively. The acetylene cluster ion intensity distributions observed under efficient clustering conditions are further characterized by unexpected features, most notably a sharp break at n = 7 and a strong magic number at n 14. The mass spectra of methyl-acetylene display a less dramatic break at n 7 and a weak magic number around n 10. These surprising structures may arise as a result of the formation of particularly stable covalently bonded molecules ions. In view of the unique properties of carbon it is possible that these ions possess spherical cage geometries reminiscent of the fullerenes.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1992
- Accession Number
- ADA251760
Entities
People
- Gopal Vaidyanathan
- James F. Garvey
- M. Todd Coolbaugh
- Stephanie Gumina
Organizations
- University at Buffalo